Light apparatus of an optical mouse with an aperture stop and the light projection method thereof

Abstract

A light apparatus of an optical mouse with an aperture stop and the light projection method thereof are described. The light apparatus has at least one image-forming lens and an aperture stop. The image-forming lens defines an interior area and an external area. The aperture stop has a pupil. The aperture stop shelters the external area of the image-forming lens. The pupil of the aperture stop corresponds to the interior area. The present light apparatus will not produce a light halo on the image detection unit of the optical mouse when the light source of the optical mouse projects a light that passes through the image-forming lens of the light apparatus. Therefore, the image detection unit clearly detects the image of the image detection surface.

1. A light projection method for a light apparatus of an optical mouse with an aperture stop, the method comprising:
 providing a light apparatus, wherein the light apparatus comprises at least two image-forming lenses and an aperture stop, and each image-forming lens has an interior area and an external area, the aperture stop including a pupil corresponding to the interior area of the at least two image-forming lenses, the at least two image-forming lenses define a light path, the aperture stop being located in the light path and between the at least two image-forming lenses and sheltering the external area of the at least two image-forming lenses; 
 wherein light from the image detection surface faces a first of the image-forming lenses, part of the light faces and is transmitted to the interior area of the first image-forming lens, and another part of the light faces and is transmitted to the external area of the first image-forming lens; and 
 passing part of the light facing and transmitted to the interior area of the first image-forming lens through the aperture stop to an image detection unit through a second of the image-forming lenses, the aperture stop sheltering the second image-forming lens from the other part of the light that faces and is transmitted to the external area of the first image-forming lens on a front of the image detection unit. 
 
   
   
     2. The light projection method for a light apparatus of an optical mouse with an aperture stop of  claim 1 , wherein the aperture stop is located between the second image-forming lens and the image detection unit. 
   
   
     3. The light projection method for a light apparatus of an optical mouse with an aperture stop of  claim 1 , wherein the aperture stop is located between the first image-forming lens and the image detection surface. 
   
   
     4. The light projection method for a light apparatus of an optical mouse with an aperture stop of  claim 1 , wherein the aperture stop is assembled on the first image-forming lens. 
   
   
     5. The light projection method for a light apparatus of an optical mouse with an aperture stop of  claim 1 , wherein the aperture stop is made integrally in one piece with the first image-forming lens. 
   
   
     6. The light projection method for a light apparatus of an optical mouse with an aperture stop of  claim 1 , wherein the aperture stop is attached to a surface of the first image-forming lens. 
   
   
     7. The light projection method for a light apparatus of an optical mouse with an aperture stop of  claim 1 , wherein part of the light facing the interior area of the first image-forming lens first passes through the first image-forming lens, and then passes through the pupil of the aperture stop to the second image-forming lens and an image detection unit. 
   
   
     8. A light projection method for a light apparatus of an optical mouse with an aperture stop, the method comprising:
 providing a light apparatus, wherein the light apparatus comprises at least one image-forming lens and an aperture stop, and the image-forming lens defines an interior area and an external area, the aperture stop including a pupil corresponding to the interior area of the at least one image-forming lens, the at least one image-forming lens defining a light path, the aperture stop being located in the light path and shelters the external area of the at least one image-forming lens; 
 projecting light from a light source of the optical mouse onto an image detection surface, wherein the light is reflected from the image detection surface and faces the image-forming lens, part of the light faces and is transmitted to the interior area of the image-forming lens, and another part of the light faces and is transmitted to the external area of the image-forming lens; and 
 passing part of the light facing and transmitted to the interior area of the image-forming lens through the aperture stop and the aperture stop sheltering from another part of the light that faces and is transmitted to the external area of the image-forming lens; 
 wherein part of the light facing the interior area of the image-forming lens first passes through the pupil of the aperture stop, and then passes through the image-forming lens to an image detection unit. 
 
   
   
     9. A light apparatus of an optical mouse with an aperture stop, comprising:
 at least two image-forming lens defining a light path, each image-forming lens having an interior area and an external area; and 
 an aperture stop having a pupil corresponding to the interior area of the at least two image-forming lenses, wherein the aperture stop is located between and in the light path of the at least two image-forming lens and shelters the external area of the at least two image-forming lenses; 
 wherein light from the image detection surface faces a first of the at least two image-forming lenses, part of the light faces and is transmitted to the interior area of the first image-forming lens and passes through the pupil of the aperture stop to an image detection unit through a second of the image-forming lenses, and another part of the light faces and is transmitted to the external area of the first image-forming lens and the second image-forming lens is sheltered from the other part of the light by the aperture stop. 
 
   
   
     10. The light apparatus of an optical mouse with an aperture stop of  claim 9 , wherein the aperture stop is located between the second image-forming lens and the image detection unit and is fixed on the image-forming lens. 
   
   
     11. The light apparatus of an optical mouse with an aperture stop of  claim 9 , wherein the aperture stop is located between the first image-forming lens and the image detection surface and is fixed on the first image-forming lens. 
   
   
     12. The light apparatus of an optical mouse with an aperture stop of  claim 9 , wherein the aperture stop is assembled on the first image-forming lens. 
   
   
     13. The light apparatus of an optical mouse with an aperture stop of  claim 9 , wherein the aperture stop is made integrally in one piece with the first image-forming lens. 
   
   
     14. The light apparatus of an optical mouse with an aperture stop of  claim 9 , wherein the aperture stop is attached to a surface of the first image-forming lens. 
   
   
     15. The light apparatus of an optical mouse with an aperture stop of  claim 9 , wherein the aperture stop is made by a sheltering material or a reflecting material.